Can animals learn language?

Koko the gorilla Koko is a 32-year old female gorilla who has stunned the world by being able to learn and use human language. Dr. Francine "Penny" Patterson is Koko’s keeper for 25 years and has taught her how to use sign language.

The Gorilla Foundation

How many words does Koko know?

Information from the website During the course of the study, Koko has advanced further with language than any other non-human. Koko has a working vocabulary of over 1000 signs. Koko understands approximately 2,000 words of spoken English. Koko initiates the majority of conversations with her human companions and typically constructs statements averaging three to six words.

My essay According to the Gorilla Foundation website, Koko is able to use more than 1000 signs, and she can understand 2000 words of English. (Source: Sept 23, 2003) OR According to the Gorilla Foundation, “Koko has a working vocabulary of over 1000 signs”. (Source: Sept 23, 2003)

Can Koko make sentences or create new words?

On Koko’s film When presented with a bracelet for the first time, Koko was able to use a combination of two existing signs, ‘hand’ and ‘necklace’, in a new combination to mean “bracelet”.

In my essay Not only can some animals communicate with human beings through sign language, they appear to have the ability to be creative as well. For example, in the film “A Conversation with Koko”, one sees how the gorilla can invent the word “bracelet” by combining the signs “hand” and “necklace”.

Alex the Grey Parrot Alex is a grey parrot who not only can imitate human speech, he can also understand the concepts behind the words (e.g. same and different, colour, shape).

The Alex Foundation

On Alex’s website Thus when shown two identical objects or ones that vary with respect to some or all of the attributes of color, shape, and material, Alex responds with the appropriate category label as to which attribute is "same" or "different" for any combination; if, however, nothing is same or different, he replies "none".

In my essay Not only can Alex the Grey Parrot understand lots of English words, he can actually respond correctly to questions about sameness and difference, e.g. whether two cubes are of the same colour. ( ticles/harvard/harvard.html, Sept 23, 2003) ticles/harvard/harvard.html

Book on Alex Pepperberg, Irene Maxine The Alex studies : cognitive and communicative abilities of grey parrots. Cambridge, Mass. : Harvard University Press.

Can Alex understand relative concepts? In Dr Pepperberg’s book, we find the following sentence on page 166: “In sum, Alex showed some comprehension of a relative concept, that of size.”

My essay Dr Irene Pepperberg has conducted a series of experiments which showed that Alex the Grey Parrot is able to understand the relative concept of size (bigger than, smaller than). (Pepperberg 1999:166)

List of references Pepperberg, Irene Maxine The Alex studies : cognitive and communicative abilities of grey parrots. Cambridge, Mass. : Harvard University Press. Yule, George The Study of Language. Second edition. Cambridge: Cambridge University Press. The Gorilla Foundation website (

Further information Consult Dr David Gardner’s webpage “Plagiarism and how to avoid it”